A fundamental task in quantum information science is to transfer an unknown state from particle A to particle B (often in remote space locations) by using a bipartite quantum operation . We suggest the power of for quantum state transfer (QST) to be the maximal average probability of QST over the initial states of particle B and the identifications of the state vectors between A and B. We find the QST power of a bipartite quantum operations satisfies four desired properties between two d-dimensional Hilbert spaces. When A and B are qubits, the analytical expressions of the QST power is given. ...
